1998 Chevy Camaro exhaust rattles

Look at where the exhaust manifolds bolt up to the flaired pipes before the cat. The cat. Should be replaced as a unit. The unit I am talking about has the catalytic converter and the two pipes I am talking about attached -- these pipes have flaired inlets that bolt up to the manifold (or header) with three bolts and springs. This is the manifold flange. The springs keep high tension applyed to the flange and keep this connection ridgid but flexable. These bolts should not be over tightened -- and sometimes, when you mess with the exhaust the springs can break - or the bolts themself can break.
Look at this area, it sounds to me that either a spring broke or the flange was overtightened and may have failed. Keep us posted